Amplifiers are utilized in a wide variety of electronic devices and systems to amplify or attenuate a signal. Track-and-hold amplifiers, such as the amplifier illustrated in FIG. 8, are commonly used in data acquisition systems because they are capable of sampling/tracking an analog signal and holding the value during some other operation, such as analog-to-digital conversion.
In various applications, the settling time of the output signal of the amplifier is an important parameter and may affect the overall performance of the electronic device. For example, in high frame rate and/or high resolution imaging applications, a shorter settling time of the output signal is required to provide the desired frame rate and/or resolution. In addition, in applications that utilize multiple amplifiers, a mismatch in settling time between the amplifiers may manifest itself as noise in the signal, which may adversely affect the final signal.
In general, the settling time may be reduced by increasing the supply current and/or decreasing the size of the sampling capacitor. Decreasing the size of the sampling capacitor, however, increases the kTC (sampling) noise, while increasing the supply current increases the overall power consumption of the device.